The present invention relates to a computer system including a management server and storage units, and in particularly to a technique for effectively using logical volumes in the storage units.
In these years, information amount to be handled by clients or users who utilize the storage units has been increased continuously, and this trend will continue certainly even in the future. The number of storage volumes in the user environment is also increased with the increase of information amount, it is therefore necessary to prepare a more effective volume management than that being presently used. Particularly for use in the operation, the reuse of volumes, which become unused, has been a serious problem for a manager who manages the storage units. In this relation, US2007/0245114 has disclosed a technique for discriminating whether an actual volume can be deleted in response to the presence or absence of access to the actual volume from a virtual volume.